Nitrocellulose composition



Patented Feb. 21, 1928.

umreo STATES PATENT- OFFICE.

CHARLES ZBOGIN, or 'rn'nzan HA'UTE, INDIANA, ASSIGNOB T COMMERCIAL SOLVEN'I'S CORPORATION, OF .TEBBE HAUTE, INDIANA, A CORPORATION OF MAR'YIAND NITROGELLULOSE COMPOSITION. 1

No Drawing.

My invention pertains to nitrocellulose compositions and relatesspecifically to the formation of plastic masses, films, and lacquers containing nitrocellulose. As is well 5 known in the art, nitrocellulose itself is unsuitablefor the formation of plastic masses (such as celluloid), films, and lacquers, on

account of its brittle non-plastic nature.

In the production of plastic masses and l0 films from nitrocellulose it has for years been ac In some cases these plasticizers have been.

used for the direct solution of nitrocellulose. In other cases the plasticizer has been incorporated with the nitrocellulose by the'aid of a mutual solvent or solvent mixture, which, in the' case of plasticmass and film production is subsequently removed by evaporation and which, in the case of lacquers, is allowed to remain until the lacquer is. ap plied. so A plasticizing agent for employment in the production of nitrocellulose lacquers and nitrocellulose films should he possessed 0 the following properties (a) It should be a solvent lose,

(b) It should be a neutral stable material which does not decompose on aging,

for nitrocellu- (0) It should be absolutely non-yolatile types of film-forming machinery, known to atmospheric conditions.

under ordinary discovered that the dibutyl 40 I have now able material foremployment as a nitrocellulose plasticizer in the productlon of plastic masses, films, lacquers, etc. Mesotartaric acid is an organlc acid having an empirical formula identical with the true tartaric acids (dextro,'laevo, and racemic) but having a different molecular configuration. It is'a white .crystalline substance melting at 140- 143. Dibutyl mesotartrate may easily be prepared'by mixing molecular proportions of-butyl alcohol and mesotartaric acid in the presence of heat and a catalyst such as hydrochloric acid gas. The yield obtainable by ordinary methods of esterification is in For ex-" ester of mesotartaric acid is a highly suit-- Application filed August 14, 1925. Serial 110. 50,259.

the neighborhood of 90% of the theoretical. Dibutyl mesotartrate," unlike the butyl esters of tartaric acid, is a crystalline solid melting at about 4850 C. It boils'at about 205 C. under 20 mm. vacuum. It is neutral to methyl orange indicator and is soluble in water to the extent of'1 2%. It is a good solvent for nitrocellulose.

The method of employment of dibutyl. mesotartrate as a nitrocellulose plasticiz'er is best illustrated by specific examples of use.

Example 1.-Pla8tz'0 masses.

In the production of plastiomasses the nitrocellulose is dissolved in a suitable sol- 1o vent such as acetone, only 'suflicient solvent being used to reduce the nitrocellulose toa viscous semi-liquid mass. Dibutyl mesotartrate is then added in amounts varying from to 300% of the weight of the-nitrocellu- "i lose, dependent on the degree of plasticity desired. The solvent mixture is then evaporated off by passing the mass over heated rolls or in other similar manner, and the plastic mass ismo'ulded under heat and prest sure.

Ewample 2. Fihn.s. In the production of films vfrom mixtures of nitrocellulose and'dibutyl mesotartrate the ingredients may be incorporated in a f manner similar to that described under Example 1. More solvent may be added to reduce the viscosity of the mass and the result-ant solution may be flowed out in shallow trays whereupon the evaporation of the solvent. causes the production of a This procedure may be modified and various those skilled in the art, may be employed. I

Ewample 3.La0guers.

-- However nitrocellulose itself in solution of sufficiently low viscosity t9 be success- .fully applied as a lacquer does not give sufiicient body to be an economicalsurface I covering.- Also. the adherence of the film amyl acetate must be present.

to the undersurface is inclined to be poor. For these and. other reasons, gumssuch as dammar, kauri, shellac, congo, and ester are incorporated in the lacquer. Pigments,

dyes, or lakes, are also ordinarily intro-j duced.

v The solvent mixture employed as a lacquer vehicle must hold both nitrocellulose quer formula in which dibutyl mesotar-' trate is present as the plasticizer follows 8 ounces nitrocellulose (lacquencotton). 4 ounces dibutyl mesota'rtrate. 5 8-ouncesgums (dammar and ester). 1 quart ethyl acetate. 1 quart butyl acetate. 1- quart benzol. a 1 quart to'luol.

If desired, various pigments may be incorporated. y

I am aware of the fact that in the past,

dibutyl tartrate and other esters e f-tartaric .acid have been'employed as nitrocellulose v e solvents and plasticizers, and I make' no solvent mixture. 7 7. 'A lacquer solution comprising nitrocel-' lulose,

solvent mixtureflcontaining was claim to the use 7 butyl mesotartrate, is an entirely"separate chemical substance having different physical and chemical properties from the esters .of tartaric acid andit ist'he'empIoyment of this specificsubstance as a nitrocellulose plasticizer to which my invention and application is \directed. 1 4

Now, having fully described my invention, I claim the following. as new and novel 1. A composition of matter comprising nitrocellulose and dibutyl mesotartrate,

2. A composition of matter comprising 100 parts nitrocellulose and 50-300- parts of dibutyl mesotartrate. I

3. A composition of matter comprising nitrocellulose,- dibutyl mesotartrate and a' solvent mixture,

4. A, lacquer *film comprising nitrocell lose, dibutyl mesotartrate and gum.

5. A lacquer film"comprising'nitrocellulose, ment',

6. A lacquer solution comprising nitrocel-r lulose, dibutyl mesotartrate, g'um, and a dibutyl mesotartrate, gum and a esters, alcohols, and hydrocarbons Y J GHARLES B'OGIN of such com-pounds. j Didibutyl mesotartrate, gum, and a pig- In testimony whereof I afiik mysignature. 1 v 

